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-   -   qtec on the 20B? (https://www.rx7club.com/1st-gen-general-discussion-207/qtec-20b-777886/)

Jeff20B 08-08-08 12:50 PM

qtec on the 20B?
 
I thought about adding a qtec to my 20B. The system will have a 3 to 1 header, then either a Borla or presilencer in the cat location, then the qtec right before the rearend, then up over the axle and into either an RB powerpulse muffler (yes I know it will be restrictive on a 20B, but the sound quality is oh so good and quiet!) or another Borla.

The point of the qtec in that location will allow it to be left open during hard acceleration and not be too deafening; dyno runs, spirited driving etc. Basically anything fun. Then when I want a civil driving experience such as cruising to the mall or whatever, I can leave it closed and not have bleeding ears when I step out. That's where the more restrictive, but very nice sounding RB muffler comes in.

You know Steve uses one of these RB mufflers on his 300HP setup. He simply welded a 3" pipe with a flange onto the 2.375" pipe right before it enters the muffler. I thought this was a stupid idea at first, but then I realized exhaust gasses tend to contract as they cool the further they get from the engine, and you can't get much further from the engine than right before entering the muffler.

His setup is turbo but mine is NA so NA rules do apply to me. However I believe I can skirt the rules with my idea. I just need to figure out which muffling device to use as a presilencer because an NA is louder than a turbo, and I don't want droaning. I know the Borla uses thinwall stainless for its pipes. The turbo guys can get away with them there in the cat location because the turbo kills like 50% of the volume but I'm not sure about NA users/not aware of anyone using a Borla there on their NA setup.

I could play it safe and base my system on the RB single pipe system with a header collected into 1 pipe before it enters the presilencer; in my case one of the 2nd gen presilencers in 2.5". Since 2.5" is inherantly louder than 2", I may need one hotdog style muffler in the mid/rear location right before the rear end (this is where the rear 2" presilencer sits in the RB dual pipe "streetport" center section, by the way, so there is enough room here for something no taller than 4" and no wider than say 6"). I'm thinking a Borla XP with a 4" shell and 2.5" core. I'd like a shortish one so there is enough room for the qtec right before the flange.

Then again the 20B does sound wonderful. I may be able to put up with the little bit of extra volume from the 2.5" pipe since there will always be a 20B note warbling away under there. What do you guys think?

Jeff20B 08-08-08 12:51 PM

Cliff notes:

I'm building a super quiet exhaust system with a qtec so when I want noise, I can have it. Therefore quietness and restriction are ok in 'quiet mode'. Thanks for reading.

Landon303 08-08-08 02:14 PM

sounds awesome- i'd like to do it on a car (wouldn't be 20b though)

Jeff20B 08-08-08 02:39 PM

Thanks. Thinking about it some more, I believe I can omit the hotdog/borla XP muffler in the rear/mid location because I can always add it later if things are too loud in 'quiet mode'. It'll save cash during the initial build and will probably sound just fine. We all know how quiet an RB single pipe system is, after all. This one will be just a touch louder, which should be perfect.

Looks like I need to start saving up for an RB '81-'82 muffler then. The coolest part about this is it's compatible with my current exhaust on the 13B with the SC. :D It has an RB road race header, modded center section consisting of a Y collector with the correct 30° angle, leading into a single 2" presilencer, then into the stock connecting pipe which then Ys back apart into duals, stock flange, and into the stock muffler. Sounds like crap! :)

openshot 08-08-08 06:36 PM

need to ask is qtec like v-tec?

RotorMotorDriver 08-08-08 07:53 PM


Originally Posted by openshot (Post 8451047)
need to ask is qtec like v-tec?

:wallbash:

:lol:

~T.J.

EDIT: Google is your friend sometimes...

http://www.quicktimeperformance.com/QTEC/index.php

openshot 08-09-08 11:19 AM

i know its a dumb thing to ask. my dad was telling me about that he used to have it on his cars back then but they did not have a motor they have a cord they pulled.



Originally Posted by RotorMotorDriver (Post 8451227)
:wallbash:

:lol:

~T.J.

EDIT: Google is your friend sometimes...

http://www.quicktimeperformance.com/QTEC/index.php


RotorMotorDriver 08-10-08 12:43 AM

Yeah. They had cable actuated ones, probably still do. QTEC is a newish term, I just called them exhaust cutouts or bypasses. I was just giving you a hard time because its NOTHING like VTEC, haha. ;)

~T.J.

PercentSevenC 08-10-08 02:33 AM

"Exhaust cutout" is the generic term. "QTEC" is the specific model from QTP, and they're electrically actuated.

RotorMotorDriver 08-10-08 04:19 AM


Originally Posted by PercentSevenC (Post 8453919)
"Exhaust cutout" is the generic term. "QTEC" is the specific model from QTP, and they're electrically actuated.

Correct. I meant newish term because its a newish product :)

~T.J.

JSmith0101 08-18-08 12:28 AM

I believe a member was running this on his 20B PP FD and melted the workings.

FBsliderseven 08-18-08 02:59 AM

haha thats what i thought...qtec would burn up as soon as you open it up.

Jeff20B 08-18-08 12:51 PM


Originally Posted by wotnartd (Post 8473399)
I believe a member was running this on his 20B PP FD and melted the workings.

D'oh!

JSmith0101 08-18-08 10:04 PM


Originally Posted by Jeff20B (Post 8474302)
D'oh!

I may put one on my 13BT swap, though. Right after the downpipe, of course, with a side exit.

Sexy.

Jeff20B 08-19-08 12:18 PM

You know, I was planning on putting the qtec further down the exhaust than the PP guy did, so maybe the workings will stay working. It's something for me to consider at least.

84stock 08-30-08 02:31 PM

This is a qtec on a rotary http://s222.photobucket.com/albums/d...ortexhaust.flv

FirebirdSlayer666 08-30-08 08:37 PM

What about a Varex muffler? It offers the same principle as a QTec would while being intigrated into a muffler.


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